1. Technical Field
The present invention relates generally to the field of network management and more specifically to discovering a network topology from routing information.
2. Discussion of Related Art
In Network Management Systems (NMS) and applications, accurate knowledge of network topology (connectivity) is needed for various network management tasks. For example, the information about network topology enables a NMS to correlate pieces of end-to-end diagnostics and monitoring information to identify failed components and performance bottlenecks. Furthermore, higher-level network management functions, such as root-cause-analysis (RCA), service-level-agreements (SLA) monitoring, and network failure impact analysis, can be done via the analysis performed on top of the monitored topology.
The technologies in network management for topology monitoring typically rely on the ability of the NMS to query every node in the network to discover network links and determine current states of the network links. For example, a network management system would discover the topology of the network by a BFS (Breadth First Search) process, i.e., iterating the process of querying a node's adjacency table that lists its neighbors and visiting its neighbors until no more new nodes (or links) can be discovered. A disadvantage of this approach is its scalability: the complexity of the topology monitoring mechanism grows linearly as the network size grows.
Therefore, a need exists for a system and method of discovering a network topology scalably from network monitoring information of a subset of nodes in the network.